Dumortierite is an aluminum borosilicate with formula Al7(BO3)(SiO4)3O and hardness of 7.

Commonly found mixed with quartzite from Peru' ,but rarely faound as blue inclusions in clear quartz.Delicate gery-blue,sometimes brownish needles like sprays or puff-balls are confined near the surface of the crystals giving an attractive blue color,that is difficult to find in quartz.

This material is normally cut in cabochon leaving the back part natural in order to preserve the thin layer of dumortierite.It comes from the Serra Espinhaçao Range,near the Vaca Morta quarry, Minas Gerais, Brazil.Completely natural ,untreated.